Abstract 653: Inhibition of MMP9 improves anti-tumor immunity by changing the tumor microenvironment to promote T cell trafficking and activation

Safety and tolerability of andecaliximab as monotherapy and in combination with an anti-PD-1 antibody in Japanese patients with gastric or gastroesophageal junction adenocarcinoma: a phase 1b study

Background

Matrix metalloproteinase 9 (MMP9) is implicated in protumorigenic processes. Targeting either stromal or epithelial MMP9 reduces the incidence of metastasis. Andecaliximab is a monoclonal antibody that targets MMP9 with high affinity and selectivity. However, no study has examined whether the inhibition of T-cell programmed death 1 (PD-1) in the presence of andecaliximab increases activated lymphocyte infiltration into the tumor, thereby increasing antitumor activity more than that in anti-PD-1 monotherapy. In this study, we assessed the safety, pharmacokinetics (PK), exploratory biomarkers, and preliminary efficacy of andecaliximab as monotherapy and in combination with nivolumab in Japanese patients with advanced or recurrent gastric or gastroesophageal junction (GEJ) adenocarcinoma.

Methods

This phase 1b study comprised four cohorts enrolling Japanese patients with gastric or GEJ adenocarcinoma. This paper concerns cohorts 1 and 4; cohorts 2 and 3 will be reported subsequently. Cohort 1 enrolled patients with human epidermal growth factor receptor 2 (HER2)-negative tumors (n=8) who received andecaliximab monotherapy (800 mg by intravenous infusion every 2 weeks (Q2W)), and cohort 4 enrolled patients irrespective of their HER2 status (n=10) who received 800 mg of andecaliximab in combination with nivolumab Q2W. Safety, dose-limiting toxicities (DLTs), PK, pharmacodynamics, and biomarkers were assessed in both cohorts.

Results

PK of andecaliximab in Japanese patients with gastric or GEJ adenocarcinoma was similar to that reported in non-Japanese patients with advanced solid tumors. Andecaliximab monotherapy and in combination with nivolumab demonstrated no DLTs in cohort 1 and 4, respectively. Toxicities were manageable and well tolerated in both cohorts. The median progression-free survival was 1.4 months (90% CI, 0.5 to 5.4) and 4.6 months (90% CI, 0.9 to not reached) in cohorts 1 and 4, respectively. The objective response rate was 50% (90% CI, 22% to 78%) in cohort 4, and in some patients, the combination therapy was effective regardless of the biomarker status.

Conclusions

The andecaliximab–nivolumab combination demonstrated a manageable safety profile and promising clinical activity in patients with advanced gastric adenocarcinoma.

NCT02862535.

Therapeutic efficacy of anti-MMP9 antibody in combination with nab-paclitaxel-based chemotherapy in pre-clinical models of pancreatic cancer

Matrix metalloproteinase 9 (MMP9) is involved in the proteolysis of extracellular proteins and plays a critical role in pancreatic ductal adenocarcinoma (PDAC) progression, invasion and metastasis. The therapeutic potential of an anti‐MMP9 antibody (αMMP9) was evaluated in combination with nab‐paclitaxel (NPT)‐based standard cytotoxic therapy in pre‐clinical models of PDAC. Tumour progression and survival studies were performed in NOD/SCID mice. The mechanistic evaluation involved RNA‐Seq, Luminex, IHC and Immunoblot analyses of tumour samples. Median animal survival compared to controls was significantly increased after 2‐week therapy with NPT (59%), Gem (29%) and NPT+Gem (76%). Addition of αMMP9 antibody exhibited further extension in survival: NPT+αMMP9 (76%), Gem+αMMP9 (47%) and NPT+Gem+αMMP9 (94%). Six‐week maintenance therapy revealed that median animal survival was significantly increased after NPT+Gem (186%) and further improved by the addition of αMMP9 antibody (218%). Qualitative assessment of mice exhibited that αMMP9 therapy led to a reduction in jaundice, bloody ascites and metastatic burden. Anti‐MMP9 antibody increased the levels of tumour‐associated IL‐28 (1.5‐fold) and decreased stromal markers (collagen I, αSMA) and the EMT marker vimentin. Subcutaneous tumours revealed low but detectable levels of MMP9 in all therapy groups but no difference in MMP9 expression. Anti‐MMP9 antibody monotherapy resulted in more gene expression changes in the mouse stroma compared to the human tumour compartment. These findings suggest that anti‐MMP9 antibody can exert specific stroma‐directed effects that could be exploited in combination with currently used cytotoxics to improve clinical PDAC therapy.